A Binary Large Object (BLOB) is a collection of binary data stored as a single entity. BLOBs typically contain image, audio, or other multimedia data. Navigation system vendors may also store map data in BLOBs.
The Navigation Data Standard (NDS) describes storing map data in a relational database. The relational database includes one or more tables that include an identifier, attributes, and a BLOB for each record in the table. Using relational databases to store BLOBs has the advantage of simplifying data access by using Structured Query Language (SQL). SQL is a database computer language designed for managing data in relational database management systems (RDBMS).
Unfortunately, relational databases are not optimized for handling BLOBs. As a result, storage space may be wasted and retrieval of the BLOBs may require several seek operations. These deficiencies are particularly a problem in embedded systems with high performance requirements and size limitations. An embedded system is a computer system designed to perform one or a few dedicated functions often with real-time computing constraints. Embedded systems include mobile telephones, personal digital assistants (PDAs), mp3 players, videogame consoles, digital cameras, DVD players, GPS receivers, navigation systems, printers, and so on.
Therefore, it would be beneficial to maintain the advantages of using relational databases (e.g., convenient query language), while improving the handling efficiency of the BLOBs, especially in embedded systems.